In the recent decade, polymer-based nanocomposite materials have attracted a great deal of attention because of their applications in various high-tech applications, such as micromechanical devices, memory storage media, chemical and biochemical sensors, display devices, and photonic band-gap materials. Generally, colloid crystals are employed either as templates for producing ordered 2D or 3D structures, (Holland, B T, Blanford, C F, Stein A. Science 1998, 281, 538; Zahidov, A. A. et al. Science 1998, 282, 897; Wijnhoven, J. E. G., Vos, W. L. Science 1998, 281, 802; Lenzmann, F., Li, K., Kitai, A. H., Stöver Chem. Mater. 1994, 6, 156) for example, in the fabrication of photonic bang gap materials or on their own right as chemical sensors (Holtz, J. H., Asher, S. A. Nature 1997, 389, 829) and devices for memory storage (Kumacheva, E.; O. Kalinina; Lilge, L. Adv. Mat. 1999, 11, 231).
Recently, a new approach to producing 3D polymer-based nanocomposites has been proposed. This method employs latex particles composed of hard cores and somewhat softer shells (Kalinina, O.; Kumacheva. E. Macromolecules 1999, 32, 4122). U.S. Pat. No. 5,952,131 to Kumacheva et al., the contents of which are incorporated herein by reference, discloses a material having a matrix composed of particles having a core resin and a shell resin. FIG. 1a demonstrates the stages in fabrication of such a nanocomposite material from core-shell latex particles. Core-shell latex particles, composed of hard cores and somewhat softer shells, are synthesized at step A. The particles are packed in a close packed array, at step B, and annealed at step C at the temperature that is above the glass transition temperature, Tg, of the shell-forming polymer (SFP) and below the Tg of the core-forming polymer (CFP). As a result, the latex shells flow and form a matrix, whereas the rigid cores form a disperse phase.
With this approach, it is known to incorporate functional components into the CFP. When the diffusion of the functional component between the cores and the shells is sufficiently suppressed, nanocomposite materials with a periodic modulation in composition are produced. It is also known to prepare materials with a direct structure in which fluorescent core particles are embedded into an optically inert matrix.
It would be very advantageous to be able to produce a nanocomposite template array that would enable one to incorporate a wide array of materials, either organic or inorganic based materials into the template and to facilitate a method of rapidly and economically producing a broad range of polymer-based nanocomposites with periodic modulations in composition and properties. Such materials would have applications in memory storage, photonic crystals, micromechanical actuators, devices for telecommunications, interference and high-refractive index coatings, bio- and chemical sensors.